AS - 1981, Biology, Herkimer County Community CollegeBS - 1984, Biology, State University of New York at AlbanyMS - 1987, Biology, Kansas State University,PhD - 1992, Biology, University of California at IrvinePost-doc - 1992-94, Carleton University, Canada

The main focus of my laboratory is the physiological ecology and comparative biochemistry of torpor in mammals. The impacts of two current challenges facing mammals that employ torpor as a survival strategy are presently being studied. One problem that my laboratory is currently investigating is White-nose Syndrome (WNS), an emergent disease that is estimated to have killed over 5,000,000 bats in the eastern USA and Canada. WNS was first observed at a single cave in New York State during the winter of 2005-2006, and has since spread to > 190 bat hibernation sites located in 27 U.S. states and 5 Canadian provinces. The fungus that causes WNS is Pseudogymnoascus destructans, and it grows on the muzzles, wings, and ears of hibernating bats. Field studies indicate that cutaneous infection with P. destructans causes mortality through the disruption of normal torpor patterns during hibernation. Studies are presently being conducted by my laboratory on the role of cutaneous lipids in the resistance to infection with P. destructans, and the long-term effects of WNS on several bat populations in New York. My laboratory is also examining the effects of recent climate warming on the hibernation and over-winter survival of eastern chipmunks (Tamias striatus).

The Evolutionary Physiology of Hibernation

Ground squirrels (Spermophilus spp.) are herbivorous rodents that hibernate for periods of up to 8 months. Stored body fats (triacylglycerols) are the sole source of energy utilized during hibernation. The goal of my research in this area is to determine the ecological factors that favored the evolution of hibernation as an over-winter survival strategy for these rodents. The physiological/biochemical basis of mammalian hibernation is unknown. My past research with Spermophilus lateralis, however, revealed that moderately high amounts of polyunsaturated fatty acids (PUFAs) are required in the diet during the summer fattening period for hibernation to occur properly in the fall. PUFAs cannot be synthesized by mammals, but most plant tissues commonly produce them. Additional studies with S. lateralis revealed that hibernation is best when the dietary linoleic acid content is between 33 and 74 mg/g. I have also demonstrated that S. lateralis has a dietary preference for food items within this range of PUFA contents, and this level of PUFA intake is maintained by free-ranging ground squirrels through their diet selection.

The Evolution of Food Storage

Red squirrels (Tamiasciurus hudsonicus) do not hibernate, they instead survive winter by feeding on conifer seeds and fungal sporocarps (mushrooms and truffles) stored during the previous summer. The ecological factors that favored the evolution of food hoarding rather than hibernation by this species are poorly understood. The goal of my research with red squirrels is to determine the ecological/evolutionary limitations of food hoarding. Four of the five conifer seed species stored by T. hudsonicus in Pinaleño Mountains of Arizona greatly decrease in nutritional quality during winter storage. My research demonstrated that the development of complicated food hoarding preferences and stored seed management strategies are required for natural selection to favor seed hoarding. Red squirrels also air dry fungal sporocarps (mushrooms) in the branches of trees before storing them. This strategy preserves their nutritional quality as long as air temperatures remain below 0o C during storage.

The Effects of Climate Change on Hibernation

Winter air temperatures have increased in the Northeast during the past 100 years, and will increase 4o C further within 70 years. One group of mammals that may be particularly sensitive to climate change is those that hibernate during winter since body temperatures during torpor are influence by ambient temperature. Eastern chipmunks (Tamias striatus) store seeds in underground burrows for winter consumption, and they reduce their rate of energy utilization with long torpor bouts. My laboratory has been conducting a long-term study on the relationship between ambient (air/soil) temperature and the torpor patterns of free-ranging T. striatus in Southeastern New York State using temperature sensitive radio-collars from November 2000 to present.

Harlow, H.J., and C.L. Frank (2001). The role of dietary fatty acids in the evolution of spontaneous and facultative hibernation patterns in prairie dogs. Journal of Comparative Physiology B., 171: 77-84.